How did alliances cause World War 1?

Answer 1

Mutual assistance pacts of all types meant that when any one country was involved in a conflict numerous others were automatically called on for and involved.
In the early 20th century the powers of Europe readied them selves for war. Every government know it would happen so they forged allegiance's.

France and Russia had an alliance for many years but in 1907 Britain joined to create The Triple Entente.

Another alliance of powers was signed in 1882 between the Kingdom of Italy, The German Empire and The Austria-Hungary Empire. This was called the Triple Alliance of the Central Powers.

There were many other Alliances between nations in Europe that effected who ended up on what side.

Austria-Hungary had recently annexed Bosnia. This angered the Russians as they believed themselves to be the leaders of the Slavic people. Russia formed an alliance with Serbia.

The act that started the war was the assassination of Archduke Franz Ferdinand, the heir to the thrown of Austria-Hungary, on 28 June 1914.

Austria-Hungary declared war on Serbia and moved troops over the border.

Russia, being allies of Serbia declared war on Austria-Hungary.

Germany, being allies of Austria-Hungary declared war on Russia and France.

Britain had pledge they would help defend Belgium from attack in the The Treaty of London.

Germany tried to sidestep the French forces and attack through Belgium. this brought The British Empire into the war.

The Ottoman Empire was an old enemy of Russia and made an alliance with The Central Powers.

Bulgaria was feeling bitter over a previous defeat at the hands of Serbia and joined the Central Powers (Germany and Austria).

The Queen of Romania was 1st cousins with the King of Britain and the Tzar of Russia and persuaded her husband to join the Entente alliance.

Britain had an alliance with Japan and the Emperor of Japan sent troops to help the British.

Italy did not join the Central Powers as they said they would in the Triple Alliance. Instead Italy joined the Entente Allies in 1915 fighting against the Central Powers.

The USA did not join the war until 1917 after a German Naval attack on The American passenger ship The Lusitania.

The war was not only in Europe but also in the colonies in African, Asia and the Pacific.

Had there been no Alliances the war would have been between Austria-Hungary and Serbia.